create project skeleton

test/test.c

@@ -0,0 +1,11 @@
+#include "../include/lsort.h"
+#include "stdio.h"
+
+int main(void) {
+    int x = 5;
+    int y = 2;
+
+    printf("%d + %d = %d\n", x, y, add(x, y));
+
+    return 0;
+}